Can a Natural Number Satisfy n ≡ 1 (mod p) for All Primes in a Large Set?

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The discussion centers on the claim that no natural number \( n \) can satisfy the condition \( n \equiv 1 \mod p_i \) for all primes in a sufficiently large set \( \{ p_{1}, p_{2}, \dots, p_{h} \} \). The counterexample provided demonstrates that choosing \( n = p_1 p_2 \cdots p_h + 1 \) indeed satisfies the condition for any set of primes, not necessarily consecutive. This proves that the initial assertion is incorrect, as the existence of such an \( n \) is guaranteed by the properties of modular arithmetic.

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Bibubo
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Let $\left\{ p_{1},p_{2},\dots,p_{h}\right\}$ a set of consecutive prime numbers. I want to show that, if $h$ is large enough, then doesn't exists a natural number $n$ such that $$n\equiv1\textrm{ mod }p_{i},\,\forall i=1,\dots,h.$$
I think is true but I have no idea how to prove it. Am I wrong?
 
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Your claim is unfortunately false. Try $n = p_1 p_2 \cdots p_h + 1$ (and the primes don't need to be consecutive either).
 

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